The disposal of waste materials, especially toxic wastes, with plasma torches is well known and has been performed in the past. In such a process, a plasma torch transfers electrical energy through a stream of ionized gases so that the gases become an electrical conductor. With such a torch, very high temperatures in the area of 10,000.degree.-15,000.degree. Centigrade can be attained.
In general, there are two types of plasma torches, one a non-transferred arc torch and the other a transferred arc torch. In the non-transferred arc torch, the electrical potential is entirely contained within the torch, i.e., between two axially spaced rings. In such a torch, hot gases are emitted from one end of the torch.
A transferred arc torch, on the other hand, can be used in which the torch tube or body is one side of an electrical field and the other side of the field is exteriorly of the torch and spaced from the torch. The transferred arc torch is the more efficient one and enables the attainment of higher operating temperatures.
A plasma torch disposal reactor raises the temperature of waste materials, including toxic waste materials, through such high levels that such materials chemically break down (pyrolysis). This breakdown can be enhanced by maintaining an atmosphere of the appropriate gas in the incinerator. As a result, the residues are usually harmless gases and solids which are suitably removed from the incinerator.
While conventional plasma torch incinerators are satisfactory in certain applications, they have their drawbacks inasmuch as the waste materials treated thereby are sometimes not presented efficiently to the plasma torch thereof so as to provide for complete incineration, pyrolysis, or melting of the waste materials. Because of such drawbacks, a need exists for improvements in plasma torch reactors and the present invention satisfies this need.
Patents relating to the field of materials incineration include U.S. Pat. Nos. 3,599,581, 3,779,182, 4,181,504, 4,582,004 and 4,615,285 and British Pat. No. 1,170,548.